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Collective Excitations of a Two-Component Bose Condensate at Finite Temperature

C. -H. Zhang·H. A. Fertig
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Abstract

We compare the collective modes for Bose-condensed systems with two degenerate components with and without spontaneous intercomponent coherence at finite temperature using the time-dependent Hartree-Fock approximation. We show that the interaction between the condensate and non-condensate in these two cases results in qualitatively different collective excitation spectra. We show that at zero temperature the single-particle excitations of the incoherent Bose condensate can be probed by intercomponent excitations.

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C. -H. Zhang, H. A. Fertig. 2006-07-19. Collective Excitations of a Two-Component Bose Condensate at Finite Temperature. https://doi.org/10.1103/physreva.75.013601

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